With the advent of digital printing capability in silver halide systems, the ability to combine information such as text, numbers, or other information, to color photographs has become possible. The use of computers and sophisticated computer software make it possible to combine digital image data originating from sources such as a digital camera, a computer image or from a silver halide film or paper, which had been electronically scanned, with additional information, then send the combined encoded data to a digital film or paper writer to produce a photograph.
The conversion of non-image wise information such as text, numbers or other graphics, commonly known as metadata, to digital information is well known in many industries. Converting analogue sound information to a digital data is also well known, and many digital still cameras and all video-recording cameras have this feature. The desire to include sound information with pictures has long been a goal. In video cameras, sound is captured with the image on videotape and replayed through a television. In still cameras, the ability to record sound exists, but the capability to embed the sound information along with the pictorial information has been elusive despite several strategies.
Akamine et al in U.S. Pat. No. 5,664,557 has disclosed a system for recording and reproducing sound as a visible 2-dimensional bar code using a thermal printer. The recorded sound can be printed onto a label and then affixed to an object such as a photograph and subsequently scanned with a bar code reader by the viewer. The reader reinterprets the bar code as sound data and then plays the sound through a speaker. The difficulty with this system is that the sound image and the pictorial image are spatially and temporally separate. In addition, if the label is affixed to the back of the image, the viewer cannot conveniently place the image in an album where it would first have to be removed in order to be interpreted. If the label is affixed to the image itself, it detracts from the image and if affixed to the album, requires its own space in the album and detracts from the aesthetic quality of the album. Hence, it is clearly more desirable for the picture to have the sound associated with it, but in an invisible way so that it not detract from the quality of the picture or album or inconvenience the viewer in any other way.
The ability to include sound information and image information has been demonstrated in the motion picture industry with the integral sound track technology. The sound track is comprised of a spatially separate ribbon of developed silver placed along side the frame containing the image. The silver sound image remains in the film by a unique step in the processing cycle so that it is not removed with the silver used to form the image. The `sound` file is written onto the film in a separate exposing step using a sound negative. The `sound` information is read from the print film by using an infrared sensor to measure the modulation of the silver image as a function of density and time. To achieve high fidelity sound images, a large range of developed silver density is required.
Because of the added complexity to the processing chemistry and the number of additional steps required to include the sound track, other strategies have evolved to overcome these problems. One such strategy has been described by Ciurca et al in U.S. Pat. No. 4,178,183 and improved upon by Fernandez et al in U.S. Pat. No. 4,233,389. These inventions replace the silver sound track with one comprised of an infrared light absorbing dye. The coupler which forms the dye is coated in the film in a 4.sup.th sensitized layer, and after exposure and development forms an infrared dye whose density is proportional to the sound signal from the sound negative. Modulation of this 4.sup.th infrared dye forming layer then produces a response similar to that of a developed silver sound track, but does not require special processing of the print film. Much like the silver sound track image, to reproduce a high fidelity sound, a wide dynamic range of infrared density is required and as a result, infrared dye densities of at least 3.0 are required in order to obtain hi-fidelity sound quality.
Hawkins et al in U.S. Pat. No. 5,842,063 teaches that the dye produced by the coupler in the layer sensitized to record non-imagewise information should absorb in the regions of the spectrum not appreciably overlapping with the regions of absorption of the other color records in order that the developed record of the digital data not interfere with the viewing of the pictorial records. To accomplish this, he proposes the use of infrared dye forming couplers coated onto the imaging element in an additional layer to the imaging records. However, he does not suggest any preferred compositions,
Due to the inherent chemical nature of organic dyes, formed in chromogenic reactions with para-phenylenediamine type color developers, the spectral absorption bands are often broader than desired. In color negative films, the unwanted absorptions of the dyes are compensated for by the colored coupler masking dyes and by additional chemistry in the film called inter-image chemistry such as development inhibitor releasing (DIR) chemistry. In the case of couplers that form infrared dyes, their chemical compositions can be such that a variety of dyes having different .lambda.-maxs, or peak absorptions, are known.
The unwanted adsorptions of the high density of the infrared dye required to produce an adequate signal to noise ratio in the motion picture print film is not an issue when the sound track and the image are spatially distinct. However, since it is desirable to have the sound image and the pictorial image in the same spatial area of the print, then the so-called unwanted absorptions of the infrared image dye must be minimized so that they do not contribute non-imagewise information to the picture.
It is, therefore, highly desirable to design a system wherein the photographic element has the ability to record metadata such as sound or other information in the same spatial area as the imagery with an `invisible dye` so that the metadata information does not degrade the pictorial quality of the image and is co-optimized with the design of the sensor which reads the invisibly encoded metadata image.
Prior Art:
Ciurca et al in U.S. Pat. No. 4,178,183 discloses a photographic element useful for forming integral soundtracks, particularly for motion picture print films, by incorporating micro-crystalline infrared absorbing dyes in a 4.sup.th sensitized layer.
Fernandez et al in U.S. Pat. No. 4,233,389 discloses a photographic element useful for forming integral soundtracks, particularly for motion picture print films, by incorporating micro-crystalline infrared absorbing dyes in a 4.sup.th sensitized layer.
Sakai et al in U.S. Pat. No. 4,208,210 discloses a photographic element useful for forming integral soundtracks, particularly for motion picture print films, by incorporating infrared absorbing dyes in a 4.sup.th sensitized layer wherein the 4.sup.th sensitized layer is sensitive to the ultraviolet light.
Powers et al in U.S. Pat. No. 4,816,378 discloses an imaging process and photographic element useful for forming half-tone color proof images by incorporating a 4.sup.th sensitized layer which contains a black or infrared dye.
Hawkins et al in U.S. Pat. No. 5,842,063 discloses a camera, film and method for recording overlapping visual and digital images in the same region of the film.
Soscia et al in U.S. application Ser. No. 09/099,616 filed Jun. 18, 1998, discloses a method and apparatus for reading invisibly printed sound data on an object, the invisible sound data being imprinted by an invisible dye from a thermal dye transfer process, an invisible printing ink, or a special photographic printing paper containing an infrared absorbing layer.
Soscia et al in U.S. application Ser. No. 09/099,627 filed Jun. 18, 1998, discloses a system and apparatus for printing invisible sound data on an object the sound data component being comprised of an infiared dye, the invisible sound data being imprinted by an invisible dye from a thermal dye transfer process.
Haraga et al in European Patent Application EP 0 915 374 A1 describes an imaging method comprising a photographic element containing a 4.sup.th sensitized layer which is designed to add invisible image information to an image.
Patton et al in U.S. Pat. No. 5,774,752 describes a method for processing photographic still images having sound information associated with them.
Akamine et al in U.S. Pat. No. 5,664,557 describes an audio data recording/reproduction system for printing optically readable code on photographic paper as a visible image.
Haga in U.S. Pat. No. 5,629,512 describes an information reading apparatus for reading invisible information encoded in an underlying layer of a recording medium which fluoresces upon being exposed to light of a specific wavelength.
Parton et al in U.S. Pat. No. 5,108,882 describes a photographic element having at least one photographic emulsion layer which is sensitized to infrared light.
Inoue et al in U.S. Pat. No. 5,313,235 describes a sound playback apparatus capable of decoding magnetically encoded sound information which has been previously encoded into an image recording medium such as a photograph.